There’s nothing more critical than having a working smoke detector in your home. Its loud, piercing alarm should wake you if there’s smoke or fire , so you and your loved ones can safely escape, or put out the fire. Smart smoke detectors go a step further, as they can send an alert to your smartphone if they sense something amiss. That way, if you’re at work, or out of town, you can call the fire department or a neighbor check on your house, to see if everything is OK. Another benefit of a smart smoke detector is that you can temporarily silence the alarm from your smartphone — so there’s no more trying to jab the Silence button with a broomstick after you set it off while cooking a steak.

Our favorite smart smoke detector is the Nest Protect. It's the most full-featured alarm, blaring out a loud siren and telling you where the problem is. It works with a lot of other smart home systems, and even performs self-checks every month. However, if you don't want to spend more than $100 on a smoke detector, then check out the Roost Smart Battery. This 9-volt Wi-Fi connected battery costs just $35, goes into any smoke detector, and alerts your phone when the alarm goes off.

Smoke Detector News (Jan)

OneLink has introduced the Safe & Sound ($249), a smoke and carbon monoxide detector that will have Alexa and Google Assistant built in. (A HomeKit version will also be available). A 10-watt speaker will also let you play tunes through the hardwired smoke detector, and, when an alarm sounds, the Safe & Sound will send an alert to your smartphone.

Best Overall

While Nest’s smoke alarm is the most expensive, it’s the most comprehensive, too. It detects both smoke and carbon monoxide, and when it does pick up something, it will not only sound an alarm, but will also tell you in what room the alert is coming from, and the nature of the alert. An LED ring on the bottom of the alarm also changes color, giving you a visual cue.

The Nest Protect comes in both wired and battery-powered versions. If you have more than one in your home, and one goes off, the others will too, alerting you to the location of the fire.

The Nest Protect also works with a wide range of smart-home devices. For example, in the event of an emergency, the Nest can automatically turn on your lights, making it easier for you to get out of your house

Among verified purchases, many complimented its performance, but acknowledged its high price. “In particular the lack of things like low battery chirps, random chirps for errors, etc, was worth an almost 100% premium for me over getting more cheap detectors,” said one reviewer.

Best Budget Option

The Roost battery is the best — well, only — option for those who already have smoke detectors, and want to make them “smart.” That’s because the Roost battery, which is Wi-Fi- enabled, sends an alert to your smartphone when the siren goes off. The second-generation battery looks and acts like the original, but has a much easier setup process.

Through the app, which can accommodate a large number of connected batteries, you have the option to silence the alarm for up to 2 minutes, and automatically send an alert to someone else. Additionally, you can link the Roost battery to other smart-home products through IFTTT, to, say, turn on your lights when the alarm goes off.

The battery is designed to last up to five years, and will work with any smoke/CO alarms that use a 9-volt battery, which includes hard-wired alarms with a 9V battery backup.

What Owners Are Saying

The original Roost Battery has only about 200 reviews on Amazon, where it gets an average of 3 stars. Among the top comments, several praised Roost’s customer service in troubleshooting issues.

“This device is pretty innovative, and a super easy, super cool way to connect up your alarm monitoring,” wrote one person.

Roost RSA-400

All-In-One Budget Option

There are no smarts in the Roost RSA-400 smoke detector itself; rather, it uses Roost’s smart Battery to connect to your Wi-Fi and alert your smartphone when it detects a problem. The RSA-400 uses both ionization and photoelectric sensors to detect fast flaming and slow smoldering fires, carbon monoxide and methane gas. The RSA-200 ($59) operates similarly, but can detect only smoke and fire. Both models require a hard-wired connection.

Onelink Smoke and CO Alarm

Works with HomeKit

Unlike many other smoke alarms, the battery inside the Onelink (which is rated to last up to 10 years) is sealed, so when the battery dies, you have to replace the entire unit. However, by that time, you should replace the smoke detector, too.

Onelink’s alarms use a Bluetooth mesh network to talk to each other, so you can get an alert throughout your entire house. Like the Nest Protect, Onelink’s alarms will tell you in which room it has detected smoke or carbon monoxide. It also has a dimmable nightlight, so you can see your way in the dark.

In addition to Alexa, the Onelink alarm also works with Apple HomeKit, which means you can have it turn on HomeKit-compatible lights when the alarm sounds. However, the Onelink is compatible only with iOS devices.

Leeo Smart Alert Smoke/CO Alarm

Smoke Alarm Accessory

The Leeo is not a smoke or carbon monoxide detector, per se; rather, this device plugs into an outlet, and listens for when the smoke alarms go off in your house. Then, it sends you an alert to your smartphone.

Because of this, you can’t use the Leeo to remotely silence your alarms, nor can it tell you from which room the alarm is sounding. However, the Leeo will automatically call a designated friend or family member if you don’t respond to the alert on your smartphone.

The small circular Leeo has an LED backlight, which is helpful in dark hallways. Plus, you can change its color using the smartphone app. Additionally, you can link the Leeo to other smart- home devices and more using IFTTT, so you can have your lights turn on when the Leeo is activated. And, it works with Android and iOS devices.

Michael A. Prospero is the reviews editor at Laptop Mag and Tom’s Guide. When he’s not testing out the latest running watch, skiing or training for a marathon, he’s probably using the latest kitchen gadget.